Bacterial tracheitis aka membranous croup
an uncommon infection of the airway that does not involve the epiglottis
Staphylococcus aureuss is the most common isolated pathogen.
Moraxella catarrhalis, Haemophilus influenzae type b, and parainfluenza virus have also been implicated in this entity, also called membranous croup.
Most patients are younger than 3 years of age when diagnosed, although older children have been affected.
Children with croup who have a bacterial superinfection (bacterial tracheitis) may reveal a necrotizing inflammatory reaction with mucosal ulcerations and microabscess formation. Some children develop a thick pseudomembrane that is attached loosely and if detached may further aggravate the airway obstruction.
The most common presentation of bacterial tracheitis is:
a preceding viral illness followed by
worsening illness with high fever
copious thick purulent secretions
toxic symptoms
respiratory distress
a brassy, productive cough is common.
Toxic shock syndrome has been seen with bacterial tracheitis due to staphylococcus aureus
The usual treatment for croup (mist, hydration, and racemic epinephrine) is ineffective
intubation or preparation for tracheotomy often is contemplated.
Chest radiography, if performed, may demonstrate patchy infiltrates, and an irregular tracheal air column often suggests purulent tracheal debris.
Direct laryngoscopy or Bronchoscopy generally is recommended to establish a diagnosis and to remove thick purulent material to improve the airway and obtain material for culture. (Fiberoptic laryngoscopy usually reveals a pale and boggy laryngeal mucosa. In bacterial tracheitis there is abundant purulent exudate and pseudomembranes. In spasmodic croup, the mucosa is inflamed, erythematous and with a velvety appearance.)
This is followed by appropriate antimicrobial treatment to cover S aureus.
Most patients require intubation but only rarely, tracheotomy.
Respiratory support is usually necessary for 2 to 3 days.
Direct laryngoscopy in the operating room typically is
employed for a definitive diagnosis of epiglottitis and to obtain cultures,
which usually reveal H influenzae type b. Antibiotic coverage of H
influenzae type b is not inappropriate for patients who have bacterial tracheitis,
but coverage for S aureus, the predominant pathogen, is more
suitable. Ceftriaxone is not the drug of choice for staphylococcal infections.
References:
Donaldson JD, Maltby CC. Bacterial tracheitis in children. J
Otolaryngol. 1989;18:101-104
Flexon PB, Gargano R, McGill TJ, Arnold JE. Bacterial tracheitis: an
unusual pathogen. Otolaryngol Head Neck Surg. 1989;100:619-620
Friedman EM, Jorgensen K, Healy GB, McGill TJ. Bacterial
tracheitis—two-year experience. Laryngoscope. 1985;95:9-11